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Journal : Jurnal Rekayasa Proses

Uji Validitas Model Shrinking Core terhadap Pengaruh Konsentrasi Asam Sitrat dalam Proses Leaching Nikel Laterit Wanta, Kevin Cleary; Petrus, Himawan TBM; Perdana, Indra; Astuti, Widi
Jurnal Rekayasa Proses Vol 11, No 1 (2017)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.23321

Abstract

Atmospheric pressure acid leaching process is one of nickel laterite processing which has a big potential to be applied in industry. The leaching process is influenced by several factors and one of them is concentration of acid as leachant. The purpose of this present study is to learn the effect of concentration of citric acid  on the use of shrinking core kinetic model. The process was done by varying citric acid concentration at 0.1, 1, and 2 M. The other operation conditions, such as particle size, solid-liquid ratio, temperature, stirring speed, and leaching process were kept constant at 125-150 μm, 0,2 sample mass/volume of acid solution, 85 oC, 200 rpm, and 120 minutes, respectively. The experimental results showed that the higher concentration of citric acid was used, the higher the percentage recovery of nickel was obtained. In addition, the validity test of shrinking core model indicated a positive impact to describe physical phenomenon of leaching process.ABSTRAKProses atmospheric pressure acid leaching merupakan salah satu proses pengolahan nikel laterit yang berpotensi untuk diaplikasikan dalam skala industri. Proses leaching ini dipengaruhi oleh beberapa faktor, diantaranya konsentrasi asam sebagai leachant. Studi ini dilakukan dengan tujuan untuk mempelajari pengaruh konsentrasi asam sitrat terhadap penggunaan model kinetika shrinking core dalam proses leaching nikel laterit. Proses leaching dilakukan dengan memvariasikan konsentrasi asam sitrat sebesar 0,1; 1,0, dan 2,0 M. Kondisi operasi lainnya, seperti ukuran partikel, rasio padat-cair, suhu, kecepatan pengadukan, dan lama proses dijaga konstan pada 125-150 μm, 0,2 massa sampel/volume larutan asam, 85 oC, 200 rpm, dan 120 menit, secara berurutan. Hasil percobaan menunjukkan bahwa semakin tinggi konsentrasi asam sitrat yang digunakan, maka semakin tinggi pula nilai persentase recovery nikel yang diperoleh. Selain itu, uji validitas model shrinking core terhadap data percobaan menunjukkan dampak yang positif dalam mendeskripsikan fenomena fisis proses leaching. 
Benefisiasi Bijih Emas dan Perak Kadar Rendah Menggunakan Palong dan Metode Flotasi Astuti, Widi; Isnugroho, Kusno; Mufakhir, Fika Rofiek; Herlina, Ulin; Nurjanah, Isti
Jurnal Rekayasa Proses Vol 12, No 2 (2018)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (424.13 KB) | DOI: 10.22146/jrekpros.35483

Abstract

A B S T R A C TBeneficiation of low-grade gold and silver ores were investigated by gravity concentration flotation methods. The ores were obtained from Way Kanan Region and Mount Burhan in Province of Lampung. In this study, gravity concentration in sluice box and flotation were performed in sequence. Effect of particle size was investigated in gravity concentration by sluice box. Furthermore, effect of various parameters in flotation operation such as concentration of collector, ore particle size, and processing time were studied. Gravity concentration in sluice box indicated that the highest recovery of gold and silver were 76.52% and 94.83%, respectively when using ore particle size of 100+150 mesh. Flotation experiments showed that the maximum recoveries of gold and silver obtained were 98.33% and 86.42%. The conditions to obtain maximum recovery in this study were -100+150 mesh of ores particle size, 25 mL/kg concentration of collector, and 25 minutes of processing time.Keywords: beneficiation; flotation, gold ore; silver ore; sluice box.A B S T R A KBenefisiasi bijih emas dan perak kadar rendah menggunakan konsentrasi gravitasi dengan palong dan menggunakan flotasi telah dilakukan. Bijih emas dan perak yang digunakan berasal dari daerah Way Kanan dan Gunung Burhan di Provinsi Lampung. Pada penelitian ini, konsentrasi gravitasi dengan palong dilakukan terlebih dahulu sebelum dilakukan benefisiasi menggunakan flotasi. Pengaruh ukuran partikel dipelajari pada konsentrasi gravitasi dengan palong. Sedangkan pengaruh beberapa variabel seperti konsentrasikolektor, ukuran partikel, dan waktu flotasi dipelajari dalam proses benefisiasi menggunakan flotasi. Pada konsentrasi gravitasi dengan palong, hasil percobaan menunjukkan bahwa persen recovery emas dan perak tertinggi secara berturut-turut adalah 76,52% dan 94,83% ketika digunakan ukuran partikel -100+150 mesh. Pada proses flotasi, hasil percobaan menunjukkan bahwa persen recoveryemas dan perak maksimum yang diperoleh adalah 98,33% dan 86,42% ketika digunakan ukuran partikel -100+150 mesh, konsentrasi kolektor 25 mL/kg dan waktu flotasi 25 menit.Kata kunci: benefisiasi; emas; flotasi; palong; perak
Studi Kinetika Proses Atmospheric Pressure Acid Leaching Bijih Laterit Limonit Menggunakan Larutan Asam Nitrat Konsentrasi Rendah Wanta, Kevin Cleary; Tanujaya, Felisha Hapsari; Susanti, Ratna Frida; Petrus, Himawan Tri Bayu Murti; Perdana, Indra; Astuti, Widi
Jurnal Rekayasa Proses Vol 12, No 2 (2018)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (671.213 KB) | DOI: 10.22146/jrekpros.35644

Abstract

A B S T R A C TKinetics study of atmospheric pressure acid leaching (APAL) process is indispensable for extractor design in an industrial scale. So far, the kinetic model used for this process is the shrinking core model. In this study, the shrinking core model was evaluated against experimental data for laterite leaching process using a solution of low concentration nitric acid (0.1 M). Variations in temperature and particle size were carried out at 303–358 K and <75–250 microns. Other operating conditions, such as pulp density, stirring speed, and time were kept at 20% w/v, 200 rpm, and 120 minutes, respectively. The model evaluation results showed that the shrinking core model was not suitable for this process because the process controlling stage is not just one stage only.Keywords: kinetics; laterite; leaching; shrinking core.A B S T R A KStudi terkait kinetika proses atmospheric pressure acid leaching (APAL) sangat diperlukan untuk proses perancangan ekstraktor dalam skala industri. Selama ini, model kinetika yang digunakan untuk proses tersebut adalah model shrinking core. Dalam studi ini, model shrinking core dievaluasi terhadap data percobaan proses leaching bijih laterit dengan menggunakan larutan asam nitrat konsentrasi rendah, 0,1 M. Variasi suhu dan ukuran partikel dilakukan pada 303–358 K dan <75–250 mikron. Kondisi operasi lainnya, seperti densitas pulp, kecepatan pengadukan, dan lama proses dijaga tetap pada 20%b/v, 200 rpm, dan 120 menit, secara berurutan. Hasil evaluasi model menunjukkan bahwa model shrinking core tidak cocok untuk proses ini karena tahapan pengendali proses tidak hanya satu tahapan saja.Kata kunci: kinetika; laterit; leaching; shrinking core
Pelarutan Emas pada Pelindian Konsentrat Emas Hasil Roasting Menggunakan Reagen Tiosianat Mufakhir, Fika Rofiek; Sinaga, J M; Oediyani, Soesaptri; Astuti, Widi
Jurnal Rekayasa Proses Vol 13, No 1 (2019)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (266.236 KB) | DOI: 10.22146/jrekpros.41519

Abstract

A B S T R A C TDissolution of gold from roasting concentrate of gold ore using potassium thiocyanate with the presence of ferric chloride as an oxidizer was investigated. The concentrate was taken from Lengkukai gold mine. Gold ore particles under 53 µm in size were roasted at varied temperature, separated using wet magnetic separator, and finally leached. The X-ray diffraction (XRD) analysis showed that there were phase changes after roasting with the emergence of new phases such as hematite, pyrrhotite, and almandine. Leaching of gold concentrate after roasting and magnetic separation showed that gold was in non-magnetic concentrate at 950oC with the highest gold dissolution of 0.95 mg/L, while magnet concentrate was completely absent. Experiments with the addition of Fe3+ ion oxidizers for 24-hour range did not have significant effect on gold dissolution. The highest gold concentration obtained of 2.29 mg/L was obtained at 12 hours with 0.1 M FeCl3. The increase of thiocyanate reagent concentrations, which showed a linear correlation to gold dissolution, produced up to 2.25 mg/L of gold concentration (12 hours at 0.3 M KSCN).Keywords: ferric ion gold dissolution; gold concentrate; roasting; thiocyanate A B S T R A KPelarutan emas dari konsentrat hasil roasting bijih emas tambang Lengkukai menggunakan reagen pelindi kalium tiosianat dengan penambahan ferric chloride sebagai oksidator telah diteliti. Partikel bijih emas dengan ukuran di bawah 53 µm di-roasting pada berbagai temperatur kemudian dipisahkan menggunakan pemisah magnetik basah dan akhirnya dilindi. Hasil analisis X-ray diffraction (XRD) menunjukkan adanya perubahan fase setelah roasting dengan munculnya fase-fase baru yaitu hematit, pirohitit dan almandin. Pelindian konsentrat emas hasil roasting dan pemisahan magnetik menunjukan emas berada pada konsentrat non magnet temperatur roasting 950 oC dengan pelarutan emas paling tinggi sebesar 0,95 mg/L, berbeda dengan konsentrat magnet yang sama sekali tidak ada. Percobaan dengan penambahan oksidator ion Fe3+ selama rentang 24 jam tidak memberikan efek yang signifikan terhadap pelarutan emas. Dari penelitian ini didapatkan konsentrasi emas tertinggi sebesar 2,29 mg/L pada 12 jam dengan konsentrasi FeCl3 0,1 M. Sedangkan penambahan konsentrasi reagen tiosianat, yang menunjukan hubungan linier terhadap pelarutan emas, menghasilkan konsentrasi besar hingga 2,25 mg/L selama 12 jam pada konsentrasi KSCN 0,3 M.Kata kunci: ion besi III; konsentrat emas; pelarutan emas; roasting; tiosianat
Pengaruh Derajat Keasaman (pH) dalam Proses Presipitasi Hidroksida Selektif Ion Logam dari Larutan Ekstrak Spent Catalyst Wanta, Kevin Cleary; Putra, Federick Dwi; Susanti, Ratna Frida; Gemilar, Gelar Panji; Astuti, Widi; Vidhian, Shinta; Petrus, Himawan Tri Bayu Murti
Jurnal Rekayasa Proses ONLINE FIRST ARTICLES
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (642.593 KB) | DOI: 10.22146/jrekpros.44007

Abstract

A B S T R A C TNickel hydroxide [Ni(OH)2] is an important compound in producing rechargeable batteries. The synthesis of Ni(OH)2 can be carried out using a hydroxide precipitation method from a solution containing nickel (II) (Ni2+) ions. In this study, the synthesis of Ni(OH)2 was investigated from the solution of extracted spent catalyst using sulfuric acid (H2SO4) solution. The selective precipitation was conducted using sodium hydroxide (NaOH) solution and the degree of acidity (pH) was varied in the range of 4?14. The operating temperature was kept constant at 30oC. The experimental results showed that the optimum precipitation conditions of Al3+ and Ni2+ ions were obtained at different pH where the optimum pH values were 6 and 10, respectively. Precipitate samples were characterized and the results showed that the purity of Ni(OH)2 in those samples was 13.1%. The XRD results indicated that the structure of precipitate still contains other impurities, such as Na2SO4, Al(OH)3 and those compounds were mutually agglomerate.A B S T R A KNikel hidroksida [Ni(OH)2] merupakan senyawa penting dalam produksi baterai yang dapat didaur ulang. Sintesis senyawa Ni(OH)2 dapat dilakukan melalui metode presipitasi hidroksida dari suatu larutan yang mengandung ion nikel (II) (Ni2+). Pada studi ini, sintesis Ni(OH)2 dilakukan dari larutan induk hasil ekstraksi spent catalyst dengan menggunakan larutan asam sulfat (H2SO4). Proses presipitasi selektif dilakukan dengan menggunakan larutan natrium hidroksida (NaOH) dan derajat keasaman (pH) divariasikan pada kisaran 4 hingga 14. Temperatur operasi dijaga konstan pada 30 oC. Hasil percobaan menunjukkan bahwa proses presipitasi ion Al3+ dan ion Ni2+ mencapai keadaan optimum pada pH yang berbeda dengan nilai pH optimumnya adalah 6 dan 10, secara berurutan. Hasil karakterisasi sampel menunjukkan bahwa kemurnian Ni(OH)2 dalam sampel sebesar 13,1%. Hasil pengujian XRD mengindikasikan bahwa struktur presipitat yang terbentuk masih mengandung senyawa pengotor lain, seperti senyawa Na2SO4, Al(OH)3 dan senyawa?senyawa tersebut saling mengaglomerasi.Kata kunci: nikel hidroksida; presipitasi selektif; spent catalyst 
Co-Authors . Aprolita, . Adil Jamali, Adil Agus Prasetya Aprimal Aprimal, Aprimal Arsyad Lubis, Arsyad Astrilia Damayanti Azhar Azhar Bambang Suharno Bayu Kurniawan Bratakusuma, D Bratakusuma, Danu Catur Rini Widyastuti, Catur Rini Dewi Purnama Sari Diah Ayu Wulandari, Diah Ayu Djoko Adi Widodo Dwi Handayani, Anggelita Eka Ayu Agustina, Himmah Sekar Endang Tri Wahyuni Fajar Nurjaman Gemilar, Gelar Panji Hendrik Setiawan, Hendrik Heni Kusumayani Heny Kusumayanti Herlina, Ulin Herlina, Ulin Himawan Tri Bayu Murti Petrus, Himawan Tri Bayu Murti I Made Bendiyasa Indah Nurul Izzati, Indah Nurul Indra Perdana Iskandar, Y Iskandar, Yusuf Isnugroho, Kusno Isnugroho, Kusno Kristian, Lian Kristian, Stefanus Lian Kusuma, Alam Budi Kusumawardani, Yustika Kusumawardani, Yustika Kusumawardani, Yustika Mufakhir, Fika Rofiek Mufakhir, Fika Rofiek Mufakir, Fika Rofiek Muhammad Amin Nova Susilowati, Nova Novira, Dinda Tri Novita, Sinta Nur Nalindra Putra, Nur Nalindra Nurjanah, Isti Nurjanah, Isti Petrus, Himawan TBM Petrus, Himawan TBM Putra, Federick Dwi Radenrara Dewi Artanti Putri, Radenrara Dewi Artanti Ratna Dewi Kusumaningtyas Ratna Frida Susanti Ria Wulansarie, Ria RTD Wisnu Broto RTD. Wisnu Broto Septriana, Ayu Setyawan, Cahya Edi shinta virdhian, shinta Shofi, Achmad Sinaga, J M Sinaga, J M Soesaptri Oediyani, Soesaptri Sofi, Achmad Suka, Ediman Ginting Tanujaya, Felisha Hapsari Tanujaya, Felisha Hapsari Tawfiequrahman, Ahmad Triastuti Sulistyaningsih Vidhian, Shinta Wanta, Kevin Cleary Wanta, Kevin Cleary Widhi Maharani Wijaya, Ardyanto Wiratni Wiratni, Wiratni Yustika Kusumawardani, Yustika Kusumawardani Zulaechah, Luluk Siti Zulaechah, Luluk Siti